Ansa Cervicalis Neurostimulation in Obstructive Sleep Apnea

2019 American Board of Sleep Medicine Junior Faculty Grant

David Kent, MD
Vanderbilt University Medical Center

Key Project Outcomes

This project was designed to evaluate the effect of ansa cervicalis stimulation (ACS) of the sternothyroid muscle on upper airway patency in patients with obstructive sleep apnea (OSA). Changes in lung volume alter the amount of downward tension the thorax and trachea place on upper airway structures. ACS pulls pharyngeal structures downward in a similar fashion, and may represent a novel neurostimulation therapy for treatment of OSA. In this project, fine-wire electrodes were used to stimulate ansa cervicalis nerves while patients were sedated in the operating room. ACS substantially decreases the amount of pressure required to open the upper airway, suggesting it has potential for stabilizing the upper airway as a neurostimulation treatment for OSA. ACS had greater effects in more obese participants, in contrast to other known surgical treatments for OSA, including hypoglossal nerve stimulation (HNS). Increasing sleep apnea severity and complete tongue base collapse decreased the magnitude of the response, but other data suggests that ACS pulls the tongue inferiorly, unloading pressure from against the soft palate. Importantly, complete concentric palatal collapse did not affect outcomes. These findings suggest that HNS and ACS have markedly different effects on the airway and that ACS may be a potential therapeutic mechanism for patients with complete concentric palatal collapse or inadequate response to HNS treatment.

Journal Articles


Quantitative Effects of Ansa Cervicalis Stimulation in Obstructive Sleep Apnea


Objective Pharyngeal Phenotyping in Obstructive Sleep Apnea With High-Resolution Manometry